Long lines, baggage fees and canceled flights: For passengers, the experience of flying today can trigger enormous stress.

But internationally, airlines are focused on another pressing problem: incidents of air rage that are on the rise.

Alcohol is among the key factors the airline industry cites as causing an increase in unruly passenger incidents. And sleep medication on long flights is adding to passengers' failure to follow directions.

But the numbers in the United States tell a different story. Despite some high-profile cases, instances of air rage and unruly passengers are decreasing.

That's partly because of how the industry classifies the incidents, and what happens when passengers break the law.

"The traveling public here is conditioned to the security environment that we're in. People know not to misbehave on aircraft because the consequences are severe," said Joshua Marks with the American Aviation Institute.

In March, the International Air Transport Association, which represents 240 airlines, will propose rule changes that will bring global laws against passengers who are unruly more in line with reglations in the U.S.

The goal is to stop flight and cab crews from having to act as a police force in the sky.